Reporting in the journal Food Quality and Preference, the researchers hailed the study as “a new way to investigate the relationship between food and beverage consumption and the improvement of human cognition.

"Two biological ingredients, caffeine and theanine, have beneficial effects on attention, which is an indispensable part of cognitive function.”

However, they also noted the small sample size and suggested further research was necessary.

A huge selection of teas can be paired with chef Puck's small and sophisticated bites, such as a savory Sourdough “Grilled Cheese” Sandwich or sweets like Dulce de Leche. Bubbly is available. The Wolfgang Puck Fine Dining Group

Traditional English tea is offered daily, with a wide variety of teas and small plates such as a ham and brie lollipop. Champagne, cocktails and a children's menu are also available. Mandarin Oriental, Las Vegas